Pulp-processing systems



Oct. 10, 1961 B. F. BAcHUs ETAL PULP-PROCESSING SYSTEMS 10 Sheets-Sheet l Filed April 16, 1956 @www j at,

.n sich sx Oct. 10, 1961 B. F. BACHUS ET AL PULP-PROCESSING SYSTEMS Filed April 16, 1956 1o shets-sneet 2 mp $74437 05x 20/ 21:0 Whig-@Tl Q PAQ Oct. l0, 1961 B. F. BAcHUs ET AL 3,003,709

PULP-PROCESSING SYSTEMS Filed April 16, 1956 10 Sheets-SheetA 5 ll/f/ Oct. 10, 1961 B. F. BAcHus ET AL PULP-PROCESSING SYSTEMS 10 Sheets-Sheet' 4 Filed April 16, 1956 /wnf/yrafs f5/4090.5 1./ 502/@ frei/V57 Oct. l0, 1961 B. F.BACHUS ETAL PULP-PROCESSING SYSTEMS 10 Sheets-Sheet' 5 Filed April 16, 1956 i ll Il l l I I..

Oct. 10, 1961 B. F. BACI-lus ET AL 3,0035709 PULP-PROCESSING SYSTEMS Filed April 16, 1956 16 sheets-sheets lll Oct. 10, 1961 B. F. BAcHUs ET AL PULP-PROCESSING SYSTEMS 10 Sheets-Sheety '7 Filed April 16, 1956 fram/7 Oct. 10, 1961 B. F. BACI-lus ET AL PULP-PROCESSING SYSTEMS Filed April 16, 1956 Oct. 10, 1961 B. F. BAcHUs ETAL 3,003,709

PULP-PROCESSING SYSTEMS Filed April 16, 1955 10 Sheets-Sheet@ Oct. 10, 1961 B. F. BACI-ius ETAL 3,003,709

PULP-PRCESSING SYSTEMS Filed April 16, 1956 A 1o sheetssheet-1o mm/706s AT5/90H05 MAX/0276 United States Patent O 3,003,709 PULP-PROCESSING SYSTEMS Benson F. Bachus, Westchester, and John F. Kruzic,

North Riverside, lli., assignors to Western Electric Company, Incorporated, New York, N.Y., a corporation of New York Filed Apr. 16, 1956, Ser. No. 578,271 3 Claims. (Cl. 241135) This invention relates to pulp-processing systems, and more particularly to systems for processing and supplying pulp to a plurality ot wire covering pulp machines.

An object of the invention is to provide new and improved pulp-processing systems.

Another object of the invention is to provide pulpprocessing systems in which pulp stock may be passed selectively through a plurality of reiiners in parallel or through the refiners in series.

A further object of the invention is to provide alternate pumping apparatus for pumping selectively from a plurality of supply chests and alternate pumping means for eiecting the same purpose.

In a pulp-processing system illustrating certain features of the invention, there is provided a plurality of refining units. Selectively operable means supply pulp in parallel to all the units and convey it from the refining units to a storage chest, and alternately supplies pulp to the reiining units in series with one another to the storage chest.

A complete understanding of the invention may be obtained om the following detailed description of a pulp-processing system forming a specific embodiment thereof, when read in conjunction with the appended drawings, in which:

FIG. l is a schematic view of a pulp-processing system forming one embodiment of the invention;

FIGS. 2 and 3 are schematic views of a control circuit for a portion of the system shown in FIG. 1;

FIGS. 4, 5, 6, 7 and 8 are schematic views of another control circuit for another portion of the system shown in FIG. l;

FIG. 9 is a schematic view of a portion of the system shown in F-IG. 1, and

FIG. l is a schematic view of a control circuit for the portion of the system shown in FIG. 9.

Referring now in detail to the drawings there is shown in the pulp stock refining system in which pulp is placed in one of or both mixers or Hydrapulpers 2 and 5 (FIG. 1) of well known design and beaten up land mixed with water sprayed thereon from a supply line 10. The resulting mixture may be pumped either by a pump 16 or a pump 17 to a chest 1. Valves 18 control water to showers of the Hydrapulpers while shutoff valves 19 control water introduced in heavy strearns to the Hydrapulpers for iilling the Hydrapulpers rapidly. Shutof valves 20 control exit of the stock from the Hydrapulpers, valves 23 and 24 control selection of which of pumps 16 and 17 is to be used, and a valve 29 directs the ilow either to a regulator 30 and the chest -1 or to a sewer (not shown) if it is decided to dump the stock.

The stock is fed from a chest 1 to either or both of pumps 3 and 4, the pump 3 delivering to a Bauer retiner 8 emptying into a chest 6 and the pump 4 delivering into a Bauer retiner 9 and a chest 7. When the refiner 8 is used alone, the stock is fed to, accumulated in and then fed from the chest 6 through solenoid-controlled air operated valves '1,1 and 12 to a pump 13, which feeds through a valve 14 to a supply line 15. Similarly, when the refiner 9 is used alone, a valve 21 is closed and a valve 22 is opened to connect the chest 1 to the pump 4 and the chest 7 is filled. Then a pump 25 pumps the stock through a valve 26 to the line 15, or a valve 27 is opened to permit the stock from the chest 7 to enter the 3,003,709 Patented Oct. 10, 1961 ICC chest 6 and be mixed with the stock there. When it is desired to run the refiners 8 and 9 in series to increase refining, the system is set up so that the stock travels through the elements 21, 3, 8, 6, 1v1, 12, 22, 4, 9, 7, 26, 25 and 14 to the line 15.

If no further refining is desired, a valve 31 is set to deliver the stock from the Bauer refiners 8 and 9 to a valve 111 set to deliver to a chest 32 or a chest 33. If further refining is desired, the valve 31 is set to deliver to a Jordan refiner 34 through valves y101 and 50, and then the pulp travels from the rener 34 through a valve 102 and the valve 11,1, and to deliver in parallel with the reiiner 34 to a Jordan reiner 41 through a valve 71. The stock travels from the rener 41 to the chests 32 and 33 through valves 72, 120 and 111. The system also may be set to deliver through the Jordan refiners 34 and 41 in series, through the Valve 7-1, the refmer 41, the valves 72, -120 and 50, the retiner 34 and the valves 102 and 11.1.

A control circuit (FIGS. 4, 5, 6, 7 and 8) for the portion of the system including the Jordon reners 34 and 41 includes a multiposition manually operable selector switch 60 (FIG. 5). -In position 1, contacts 61 are closed to energize a solenoid 63 to actuate a pneumatic cylinder (not shown) to swing the valve 50 to connect the valve 101 to the Jordan reliner 34 to open limit switch 64 and close LimitV switch 65 to deenergize relay 70 and energize relay 62 (FIG. 5). A selector switch (not shown) is actuated manually to energize solenoid 66 (FIG. l) to turn valve 31 to connect valves 14 and 101, limit switch 67 being opened and limit switch 68 being closed `to bring relay 69 (FIG. 6). Switch 73 (FIG. 6) is closed manually to energ'ze relay 74 to close contacts (FIG. 4) to set up a motor-starting circuit 76 (FIG. 5) of a well known design, switch 77 (FIG. 6) being 1 stopping switch for the circuit 76. Contacts 81 and 82 to -the motor-starting circuit 76 are controller-handlecontrolled for direction of running of a motor 91 for the Jordan rener 34. Valves 71 and valves 72 must be closed to protect the idle Jordan reiiner 41 from jamming so valve-actuated limit switches 83 and 84 (FIG. 5) are provided in series to relay 85 having contacts 86. Also, the valve 120 must close oft -lines 124 and y125 and in so doing limit switch 87 (FIGS. 1 and 6) is closed to energize relay 88 `to close contacts 89. When all these things have occurred, relay 94 (FIG. 6) is energized to energize relay 95 to close contacts 96 (FIG. 4) to the starter circuit 76, which locks in and energizes relay 93 (FIG. 4) by circuit means. Energization of the relay 93 results in energization of a relay 92, which completes the circuit of motor 91. The motor 91 then runs as an inductance motor and spins its exciter-generator component K90, which generates D.C. voltage to the ield of the motor 91. When the D.C. voltage reaches a certain predetermined value, the motor 91 is then operated as a synchronous motor. When motor 91 is started, relay 98 (FIG. 4) is energized to close contacts 99 (FIG. 6) to energize valve controlling solenoidsV 104 and 105 to open the valves 101 and 102 to the Jordan rcfncr 34, thus insuring that the refmer is running before pulp stock is-delivered thereto.

The valve 101 opens limit switch 106 (FIG.Y 5) and closes limit switch 107, and the valve 102 opens limit switch 108 and closes limit switch 109. This drops out relays 112 and 113 and brings in relays 114 and 115, whose contacts 116 and 117 with contacts 118 of relay 98 lock in the motor 91. In Position 1 as described, the pulp stock is processed by only Jordan -rener 34 and is delivered to valve 111.

In Position 2, the Jordan circuit is set up in a similar fashion to that of Position 1 to run only the Jordan rener 41. Selector switch contacts 119 are closed to 3 Y energize Isolenoid 1-26 to move valve 120 to connect lines 124 and 125, valves 101 and 102 are closed. Valves 71 and 72 are opened by the motor circuit for renner 41 and switches i128 and 129 (FIG. 5) are closed to lock in motor 167. Position 3 of the selector switch 60 closing contacts 61 and 141 is for vrunning both reiners 34 and 41 in parallel, and energizes solenoids 63 and 126. Then start switches 73 and 154 are closed to start lthe motors and open valves 71, 72, 101 and 102. If renner 41 drops out from trouble, it closes valves 71 and 72 and reiner 34 would continue to run. This occurs by relay 155 (FIG. 7) dropping out to deenergize solenoids 157 and 158 and pulp isV prevented from wrecking the down reiiner. Similar circuit means protects the reiiner 34.

Position 4 is for running the reners 34 and 41 in Series. Selector switch contacts 145 (FIG. 6) are opened to keep valve 101 closed. Contacts 156 are closed to bring in relay 166 to interlock the two rener motors 91 (FIG. 4) and 167 (FIG. 7) through contacts 151 (FIG. `8) and 152 (FIG. 5) so that if either motor is knocked out, the other also is stopped. Valves 50, 101 and 120 are set'so that stock ows from rener 41 through valves :120 and 50, and switches 87 and 64 are closed to bring in relays 70 and 88. The motors 91 and 167 are started and Yrelay 98 (FIG. 4) is brought in to energize solenoid 105 to open valve 102. Valve 102 closes limit switch 108 to bring in relay 113 to close contacts 178. Relay 155 in parallel with motor 167 brings in solenoids 157 and 158 to open valves 71 and 72, which close limit switches 12S and :129. This locks in the motor 167, the motor 91 being locked in by the limit switch 108. If -any of the valves 50, 71, 72, 101, 102 and 120 is not in its proper position, the motor circuits are not locked in and both refiners 34 and 41 drop out.

Control rheostats in electronic clutch control units 191, 192, 193 and 194 (FIGS. 2 and 3) of a well known vtype -for stock pumps 3, 4, 13 and 25 are provided. To start any of these pumps, the rheostat which controls a clutch of that pump must be at zero to prevent clutching and 'the rheostat closes one of a pair of pairs of limit switches 204, 230, 205, 208, 207, 210, 206 and 209 associated with -that'pump and opens the other limit switch of that pump. For example, lto start reiner 8, the rheostat on pump 3 is placed on zero to close switch 204 and open switch 230. The retner 8 is actuated by the operator by conventional means (not shown) to open the -jaws thereof and this closes limit switch 201. Manual momentary switch 212 is closed to bring in relay 213 to close holding contacts 214 and close contacts 215 to bring in relay 216, which is a contactor for a conventional motor controller 217. This starts a motor 218 land, after a vdelay inherent in controller 217, closes contacts 219 to actuate a controller 222 to start a motor 223 of the Bauer renner 8.

The controller 222 closes contacts 220 and a clutch control 224 of -the pump 3 is actuated to close contacts 225. This brings in relay 226 to close contacts 227 and 228 to energize solenoid 229 to actuate air cylinder 240 to open valve 21. The valve 21 closes limit switch 232 to lock in the relay 213, and the clutch lof the pump 3 then is actuated by the operator through control unit 191 and the jaws of Vthe rener 8 are closed by the operator. When the rheostat for the clutch of the -pump 3 is moved off zero, lthe limit switch 204 is opened and the limit switch 230 is closed to bring in relay 235 to close contacts 236 to energize solenoid 237 to actuate an air cylinder 243 to open valve 238. Pulp stock then goes from Vchest 1 through reiiner 8 to chest 6.

The pulp may be pumped from the chest 6 to the valve 31 by the pump 13. To do this, the yrheostat of control unit 193 `is set to zero to disengage the clutch for `4the jpump 13 completely, which closes switch 207 and opens switch 210. Then a valve V517 is closed -to close limit switch 254 to energize relay 252 to close contacts 253. Manual switch 260 is actuated to close contacts 262 and open contacts 261. This energizes relay 263 .to close contacts 264. Limit switch 210 opening drops out relay 267 to close contacts 268. Manual switch 270 is actuated to open contacts 271 and close contacts 272 -to energize relay 273. Relay 273 actuates relay 275 which operates solenoid 276 to actuate air cylinder 277 to swing valve 111 to connect conduit 278 .to the chest 33. The valve 111'closes limit switch 281 to energize relay 283, and opens limit switch 282. The relay 283 actuates contactor relay 284 to start Water supplying pump 285. Thus, contacts 286, 287 and 288 are closed to energize relay 289 lto close contacts 290 to energize solenoid 291 to actuate air cylinder 292, which swings valve 14 to connect pump 13 to valve 31 and closes limit switch 293 and opens limit switch 294. The relay 289 also closes contacts 297 to energize solenoid 298 to open valve 12 thereby closing limit switch 299. Manual switch 300 is closed to energize solenoid 30-1 to actuate air cylinder 302 to open valve 11 to open limit switch 303 Vand close limit switch contacts 304 and 305. This energizes relay 308 through contacts 309 and relay 308 starts motor 310 of pump 13. The operator then actuates clutch control unit 193 to start pump 13. This rheostat closes limit switch 210 and opens limit switch 207. When motor 310 is energized by relay 308, the relay 308 also energizes relay 313 through conytacts 314. Contacts 315 and 316 are closed so relay 273 is not dropped out by opening of limit switch 207. Since pump 25 is not being run, its clutch rheostat is at zero so that the limit switch 209 is closed and contacts 321 of relay 275 have been closed, a water regulating solenoid 322 and a solenoid 323 vare energized. The solenoid 323 closes limit switch 324 to provide a holding circuit for the relay 273. A switch 341 may be actuated to drop out relay 342 to stop the reliner 8 and stock pump 13.

Similarly the pump 13 may be used to pump to stock chest 32 by pressing momentary switch 345 after closing valve 582 by conventional means (not shown) to close limit switch 583. The switch 583 energizes relay 351 to close contacts 352. Then the relay 342 is operated to set up relay 275 to operate solenoid 355 to actuate an air cylinder 356 to reverse th valve 111 to feed the pulp to the chest 32.V The valve 1111 closes limit switch 282 to energize relay 358, which energizes contacter relay 359 to energize motor 360 of a conventional Water supply regulator (not shown) to the chest 32. Relay 359 also closes contacts 361, and when relay 342 was actuated it energized relay 366 to close contacts 367, relay 289 is actuated. This actuates stock pump 13 as described above, which pumps pulp from the chest 6 to the chest 32.

To operate only the Bauer rener 9, the rheostat of pump 4 is turned to zero to close limit switch 205, the operator opens the jaws of the rener 9 to close limit switch 370, closes momentary switch 371, to energize relay 372 which energizes relay 373. 'Ihe relays 372 and 373 close contacts 375 and 376 to start a time delay circuit 377 to start motors 378 and 379. A controller unit 391 of the motor 379 closes contacts 392. The relay 373 also actuated control unit 192 to start pump motor 393 of pump 4. The unit 192 closes contacts 395 to energize relay 396 to close contacts 397 and 398. The contacts 397 actuate solenoid 399 to actuate air cylinder 400 to turn valve 22 to connect chest 1 to the pump 4. The valve 22 closes limit switch 405 and opens limit switch 406. The limit switch 405 and contacts 407 of relay 396 form a holding circuit for relay 372. Then clutch to pump can be engaged and jaws of refiner may be closed, which opens switch 370 but the relay 372 is held in by switch 405, contacts 407 and holding contacts 412. Then the operator moves switch 260 to open contacts 261 and close contacts 262, which energize relay 382. The relay 382 closes contacts 333. Then the circuit is set up to feed by the pump 4 from the chest 7 to the chest 32 or 33 in the same manner as the pump 13 was set up to pump from the chest 6 to either chest 32 or 33, the circuit for the pump 25 being analogous to that for the pump 13.

To pump the stock to the refiners 8 and 9 in parallel, both the circuits to the refiners are set up as described hereinabove in pumping to the chest 6 and 7. Then the stock is pumped from either the chest 6 or the chest 7 as described above.

To run the renners 8 and 9 in series, switch 421 (FIG. 2) is set manually in a position opening contacts 422 and energizing an indicating lamp 423. This blocks solenoid 399 to keep cylinder 400 in a condition blocking ot conduit 426 from the pump 4 and connecting conduit 427 to the pump 4. The switch 421 also closes contacts 429 (FIG. 3) to energize solenoid 301 to open valve 11 to open limit switch 303 and close limit switches 304 and 305. Switch contacts 200 are closed manually. Rheostat of control unit 191 is setto zero to close limit switch 204 and jaws of rener 9 are opened to close limit switch 232. Then switch 212 is closed to energize relay 213 to energize relay 216 to start pump 3. The relays 213 and 216 also start motors 218 and 223 of the reiiner 8. The controller 222 also closes contacts 220. The unit 191 also closes contacts 225 so that relay 226 is energized to close contacts 228 which picks up solenoid 229 to open valve 21, which closes limit switch 232 to lock in the relay 213. The clutch rheostat of the pump then may be actuated to supply power to the pump and open the switch 204. Also, the jaws of the re-incr 8 are closed to start grinding, which opens switch 232. 'I'he pulp and water then accumulate in chest 6.

To start retiner 9, clutch rheostat of stock pump 4 is on zero to close switch 205 (FIG. 2) and the jaws of the renner 9 rare open fully to close switch 370. Then, momentary switch 371 is closed to energize relay 372 which energizes relay 373 to start motor 393 of stock pump 4. The relays 372 and 373 close contacts 375 and 376 to control 377 to sequentially start motors 378 and 379. The controller 391 closes contacts 392 and pump control unit 192 closes contacts 395 to energize relay 396. Limit switches 406 and 305 and contacts 407 of relay 396 lock in relay 372. Now clutch of pump 4 is actuated to drive pump and jaws of reiiner 9 may be closed and switch 370 is opened. Now the pulp is pumped from chest 6 by pump 4 to retiner 9 and accumulates in chest 7. Then the pump 25 may be brought in as described above to pump to either the chest 32er 33.

lf the valve 31 is set to connect the conduits 15 and 441, the pulp from the Bauer refiners 8 and 9 may be fed to the Jordan renners 34 and 41. 'Ihe pulp may be fed from either Vof the chests 6 or 7 to either the Jordan reiner 34 alone, the Jordan rener 41 alone, the refiners 34 and 41 in parallel or `these two reners in series to the chest 32 or 33. The pulp also may be fed through the refiners 8 and 9 in series and then through either the reiiner 34 or the reliner 41 or the rener 34 and the refiner 41 in series or in parallel.

A key switch 461 (FIG. 10) may be set to actuate either a pump 462 or a pump 463. Assuming the switch closes contact 464 and opens contacts 465, the pump 462 will be actuated by pressing momentary start switch 466 to energize relay 467, which locks in through contacts 468. Also, relay 469 is energized to close contacts 470 and 471 and relay 475 closes contacts 472 and 473. Relay 48-1 is energized to start motor 482 to run pump 462. Valve solenoids 483 and 484 actuate air cylinders 485 and 486 to set valves 486 and 487 to connect conduits 53 and 489 to the pump 462. The Valve 486 opens limit switch 491 and closes limit switch 492. The valve 487 opens limit switch 494 and closes limit switch 495 to light an indicator lamp 493.

A selector switch 501 (FIG. l) may be set with both contacts 502 and 503 closed to ldeliver stock from both chests 32 and 33, may be set with only contacts 502 closed to deliver stock -from only chest 33, and may be set with only contacts 503 closed to deliver stock only ffrom chest 32. Assuming the switch is set to close only contacts 503 and contacts 502 are open, momentary switch 505 is closed by the operator to energize relay 506 to lock in through contacts 507, close contacts 508 and 509 and open contacts 510. The contacts 508 and 509 energize solenoids 515 and 5'16 to open valve 517 and actuate air cylinder 518 to turn =valve 519 to connect return conduit 520 Ifrom a pulp supplying loop 521. Valve 517 opens limit switch 254 and 525 and closes limit switch 526. The relay 506 also closes contacts 531 to energize relay 532 to close contacts 533 to provide a parallel limited time holding circuit when it is desired to shift from delivery from chest 32 to chest 33. Now the pulp stock delivers from chest 32 through an agitator 541 to the pump 462, then through the loop `521 which keeps a supply pipe 542 leading to a group of pulp-using machines (not shown) lled with the pulp stock under pressure. Surplus stock not needed by the pulp-using machines travels on back to the chest 32.

`Overload relay 543 in the circuit to motor 482 opens contacts 544 if the motor 482 is overloaded. This drops out relay 469 to make contacts 545 and opens contacts 470 and 471 to ldrop out relay 481 to ydeenergize the motor 482. Then, relay 475 being still energized, solenoids 546 and 547 actuate air cylinders 548 and 549 to turn valves 486 and 487 to deliver stock to and from pump 463. Also, relay 551 is energized to start motor `552 to drive pump 463. The valves 486 and 487 close switches 491 and 494 to light indicator lamp 553 and open switches 492 and 495 to darken lamp 493.

When relay 469 deenergized, it closed contacts 561 to -actuate a flasher 562 of a well known type, previously both the contacts 561 and contacts 563 being open. This gives a signal to the operator that one of the pumps 462 and 463 needs attention. Now stock is tiowing from chest 32 through pump 463 `and through the loop 521.

If selector switch is set opening contacts 464 and closing contacts 465, the pump 463 is started by pressing switch 466 and pumps #from chest 32 similarly to the above-described pumping by pump 462. Also, if motor 552 of pump 463 should be overloaded, the valves 486 and 487 will be shifted to pump 462, pump 462 started automatically, and warning asher 562 actuated.

To pump from chest 33, switch 501 is set with contacts 503 open and contacts 502 closed, switch 505 is closed momentarily to energize relay 571 to lock in through contacts 572, close contacts 573 to energize solenoid 574 and also closes contacts 575 to energize solenoid 576. The solenoid 574 actuates air cylinder 577 to feed pulp from the loop 521 to chest 33. The solenoid 576 actuates air cylinder 581 to open valve 582. The valve 582 opens limit switch 583 and closes limit switches 584 and 585. The valve 519 opens limit switch '586 and closes limit switch 587 to an indicating lamp 588 and darkens lamp 589. The relay 571 also closes contacts 591 to actuate relay 592 to close contacts 593 to provide limited delay 'action in swinging from chest 33 to chest 32 whenever this is done. This is `done through holding contacts 594 and the limit switch 525. Similarly, in switching from chest 32 to chest 33, the solenoid 515 is maintained energized until'the Valve 582 opens and opens limit switch 584 to drop out relay 532, the relay 532 having holding contacts 596, the relay 506 also having contacts 598 to originally energize relay 532.

The pump "13 pulls stock from the chest 6, and the valve 27 may be opened to permit mixing between chest 6 and 7. The pump 25 is used if stock from the chest 6 is supplied to the chest 7, and the pump 13 if chest 7 delivers to chest 6. Pulp stock in either chest 32 or chest 33 may be delivered either by pump 463 or by pump 462 in parallel therewith to a supply line 542 leading to pulp covering machines. Assuming that chest 33 and pump 463 are supplying the pulp stock, the stock goes through valves 582, 486, the pump 463, a valve 487, a pipe 489 519 back to the' chest 33. By Yreversing the'valves 486 and 487, the pump 462 can be used, and either of the pumps can be usedalsoV to supplystock from the chest 32.

To feed the loop 521 simultaneously from both chests 32`and 33, relays 469 yand 47S being deenergized contacts A561 and S63 Iare closed, and flasher '562 is running to Yopen and close contacts 611 to put lamp 612 oft and on. AS- suming selector switch 461 is set closing contacts 464 to run stock pump motor 482 to drive pump 462, start switch 466is closed momentarily to energize relays 469 and 475 to stop nasher 56-2`and close contacts 47@ to pick up motonstarting relay 481 and actuate the solenoids 483 and/484 to Connect valves 486 and 487 to pump 462. VLimit switches495- and 492 being closed to light lamp 493. The switch 466 also energizes relay 467 to close holding contacts 468 and also close contacts 613 to permit'pumping from chests,'th `e pump 462 being energized. The selector switch, 501 is set closing both contacts 502 and 593- and switch 595 is closed momentarily to ener- -gizeV relays and 571 toV close contacts 5i37, 598, 531, 568 and l569, and contacts 57.2, '591, 573 and 575, respectively. As a result relays 532 and 592 are energized, which close contacts 533 and 596, and contacts 593 and 594, respectively. Consequently, solenoid 515 yis energized to open valve 517 and solenoid 516 is energized to swing valve -,5,19 to feed to chest '32. The contacts 510 opens up'to prevent ener-gization of solenoid 574. The 'relay 571 closes contacts 575 to energize solenoid 576 to open valve 582 to -feed from stock chest 33. The valves 517 and 519 close limit switches 526 and 58610 light indicating lamp 589. This indicates that the return from the loop y521 is to chest 32. if the valve 519 were a fourway valve, the return from the loop could be to both chests -32 `and 33 or the chest 33. By pumping yfrom both chests 32 and 33, the stocks' ofthe two chests are blended to keepquality of the Iresulting stockrhigh. When limit -switches 254 Iand 583 are opened, no pumping from the renner systems to the chests 32 and 33 can beefected.

The above-described apparatus provides great flexibility'and ease of maintenance of the renners and pumps to the loop. For example, any number of refiners, from one to four may be used either inl series or in parallel.

It is to be understood that the above-described Yarrangements Iare simply illustrative of the application of the principles of the invention. VNumerous other ar- Vrangements may be readily devised by those skilled in the art which will embody the principles of the invention and `fall within the spirit and scope thereof.

What is claimed is: p 1. In a pulp-processing system for processing and delivering pulpof selected degrees of rennement, which includes a source of supply of pulp stock, a nrst pair of pulp renners, a second pair of pulp renners, and storage means for receiving pulp delivered from the renners, the improvement which comprises nrst directing means operable for advancing selectively the stock from the source of supply of pulp stock to either one of the nrst pair of pulp renners to renne the pulp stock at a predetermined rate to obtain pulp stock having a nrst desired degree of rennement, Valves in the nrst directing means being selectively positionable for directing the pulp stock to the nrst pair of pulp renners in series in order to obtain a higher degree of rennement of pulp stock as compared to the nrst desired degree of rennement obtained by using either one of the nrst pair of pulp renners, the valves in the nrst directing means being alsoselectively positionable for directing the pulp stock to the nrst pair of pulp renners in parallel to increase the rate of the pulp stock being processed in a certain period of time while maintaining the nrst desired degree o f rennement; intermediate directing means operable for advancing the pulp stock from the nrst pair of the pulp renners selectively to said storage means or to the second pair of pulp renners; second directing means operable tor' advancing'selectively Vthe pulp stock from the inter- `'mediatevdirecting means to either one of the second pair 'of pulp renners in order to obtain a greater degree of rennement of the'pulp stock as compared tothat obtained -from Vthe nrst pair of pulp renners, the degree of rennenient varying in accordance with the degree of renne- Vvment obtained in the nrst pair of pulp renners, Valves in the second directing means being selectively positionable for directing the pulp stock from the intermediate directing means through the second pair of pulp renners in series in order to obtain a yet higher degree of rennement as compared to the degree of refinement obtained by using either one of the second pair of pulp renners, the valves in the second directing means being also selectively positionable for directing the pulp stock from the intermediate directing meansthrough the second pair of pulp renners in parallel, said second directing means also being for advancing the pulp stock from the second pair of the pulp renners, connected Vin any preselected arrangement to the intermediate directing means, to said storage means; and'electrical controlmeans associated with the nrst, the Vintermediate and the second directing means, the control means being selectivelyv actuatable for operating the nrst, the intermediate and the second directing means so thatthe pulp stock is advanced to a preselected arrangement of the nrst pair and the second pair of pulp renners to obtain in a desired period of time a desired volume of pulp stock having a desired degree of rennement. f

2. Apparatus according to claim 1, wherein the nrst directing meansV include a pair of intermediate storage means normally connected individually to the output of each of the nrst pair of pulp renners so that when the nrst pair of pulp renners are in series they are interconnected through at least one of the intermediate storage means, and means for selectively interconnecting lthe intermediate storage means to selectively increase the volume of storage ofl thevpulp stock delivered by either one of 4the nrst pair of pulp renners, said intermediate storage means being also connected to the intermediate directing means in order to bypass the second of the nrst pair-of pulp rennersconnected in series so as to admit a desired amount of partially renned pulp stock to the output pulp stock of the second of the nrst pair of pulp renners connected in series to obtain a desired degree of refinement of pulp stock being advanced by the interv mediate directing means. V

3. vApparatus denned in claim 1, wherein the storage means comprises ai plurality of stock storage chests, valve means for directing the pulp stock from the second directing means selectively to the storage chests individually to maintain separate the pulp stock of the desired degrees of rennement, or in parallel to selectively increase the'storage volume and to admiX the pulp stock of various degrees of rennement in any desired proportion, and delivery directing means for advancing the stock to a pulp-utilization device from the storage chests selectively individually and in parallel to selectively control the rate of delivery and the degree of rennement of the pulp stock being delivered to the pulp-utilization device.

References Cited in theY nle of this patent UNTTED STATES` PATENTS 

